Each patient was given a "risk score" that relates to the "intended to be seen by date".
If a patient has waited their allocated time, plus 50 per cent longer they will score 1.5 - any patient with a greater score is deemed to be at clinical risk.
If they have waited double their allocated time they score 2, and so on. There were 455 patients assigned to the Waitakere clinic with a risk score of 1.5-2, and 582 in the 2-3 bracket.
Patients who had waited between four and five times longer than the period requested by the treating clinician numbered 116, with 51 patients with a risk score of 5-6, and 22 waiting between six and seven times longer than allocated.
People have been coming to harm from this.
Dr Shenton Chew, a fellow of the Royal Australian and New Zealand College of Ophthalmologists and member of the ADHB steering group, said risk scores were an imperfect measure, given some patients who waited less time would be at greater risk than those with higher risk scores.
Determining whether patients' health suffered as a direct result of delays was a grey area, he said, and the few cases with the highest risk scores had been reviewed with nothing "hugely alarming" found.
"But what we can say is using logic and common-sense - and even the occasional patient where an incident has been lodged on their behalf - people have been coming to harm from this. I can't give you data at this stage, but surely that will become available from the DHB at some point."
An ADHB spokesman said cases were still being reviewed but to date the DHB was not aware of any patients who had suffered an "adverse health outcome" because of the delays, and patients who had waited the longest had been assessed.
Since the start of ADHB's recovery plan in March the Waitemata waiting list is being cut by an average of 70 patients each week, and was down to 1232 at the start of this week and on track to be cleared by September.
Chew said ADHB had done a good job in addressing the problem through the steering group, and was "leading the way" in what was a national problem, with DHBs struggling to keep up with an ageing population and new treatments like Avastin injections that require frequent follow-up appointments.
The issue came to a head at Southern DHB when it was revealed in November that 30 patients suffered partial loss of sight because of delays, with a further 4600 people receiving letters confirming their eye operations were overdue.
The following month the Ministry of Health announced $2 million in additional funding to help DHBs clear backlogs. Health Minister Dr Jonathan Coleman's office referred questions to the ministry, which said in a statement that DHBs were already implementing plans to clear backlogs and improve services.
A national leadership programme is being developed, a national ophthalmology advisory group will be up and running by the middle of the year, and a new tool to prioritise access to services is being trialled.
"There had been variable responses by DHBs across the country to the rapid growth in demand for eye services," the statement said. "Ophthalmology services are highly-specialised, which made it difficult to swiftly expand services."
David Clark, Labour's health spokesman, said the delay figures were shocking and boiled down to a lack of resourcing to deal with an ageing demographic.
"People are being left to a significant visual impairment and one can easily imagine that the sight of many will be getting worse. The waiting list in the south we know allowed people to go blind, and I would hope that's not the case here but fear that it might be for some people."
Details of new health funding will be announced as part of this month's Budget. Last year the Government outlined an extra $2.2 billion over four years with a large portion going to DHBs to cope with an ageing population and record immigration.
In a speech delivered on Thursday, Coleman said the May 25 Budget would include new spending, including on mental health and addiction services.
Waitemata DHB ophthalmology patients
• 1356 waited for follow-up treatment long enough to be deemed to be at clinical risk.
• 116 of those patients waited four to five times longer than period requested by the treating clinician.
Source: Steering group documents, February 16, 2017
